Loud wining sound
#16
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Have you tried clutch depressed and transmission in gear vs. out of gear with clutch depressed? Even though the clutch is down I wonder if its possible that the transmission input shaft is still spinning with the engine is there is no real resistance (IE: in gear).
To answer your question earlier - the pilot bearing is spinning when the car is not in gear. The thrust / throw out bearing spins when you have the clutch depressed. Although in its resting state I wouldn't be surprised if it is still spinning, just without much load applied.
To answer your question earlier - the pilot bearing is spinning when the car is not in gear. The thrust / throw out bearing spins when you have the clutch depressed. Although in its resting state I wouldn't be surprised if it is still spinning, just without much load applied.
#17
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#19
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So I've decided I'm going to change the gearbox oil to see if it helps at all. Was thinking of going with Motul Gear 300 Gearbox Oil - 75W90. On amazon one says limited slip deferential and the other doesn't. Which do I need? I'm thinking the 1st one. Sorry... I'm a newbie. Mine is a C4 6 speed manual
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Bobcatt250 (11-25-2021)
#21
Race Director
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So I've decided I'm going to change the gearbox oil to see if it helps at all. Was thinking of going with Motul Gear 300 Gearbox Oil - 75W90. On amazon one says limited slip deferential and the other doesn't. Which do I need? I'm thinking the 1st one. Sorry... I'm a newbie. Mine is a C4 6 speed manual
https://www.amazon.com/Motul-Gear-30...otul+300+75W90
https://www.amazon.com/Motul-75w90-L...otul+300+75W90
https://www.amazon.com/Motul-Gear-30...otul+300+75W90
https://www.amazon.com/Motul-75w90-L...otul+300+75W90
(My advice would be to just use the Porsche fluid as it will be miscible with the fluid that is in the transmission currently and properly suited for use with the transmission. There is no need to question whether you need LSD compatible fluid or some other kind.)
When trying to identify a noise source be sure the A/C is off and the radiator fans are off. The fans run all the time the A/C is on even if the engine is cold.
If the noise is present from a cold start one thing you can do is remove the serpentine belt -- make a diagram of the routing of the belt and its direction of rotation so you can reinstall the belt the same way it came off -- and start the engine and let it idle only long enough to confirm the noise is absent or still present.
If absent then likely an accessory drive idler/tensioner roller bearing is bad (noisy and noisy is bad) or an accessory drive is bad. Most often in this case the water pump is the guilty accessory drive.
Check all for any excessive play. The water pump may not have lots of play but it can have -- at least in my experience -- a bit more play than the other drives which essentially had none.
Also, if the belt has a sharp edge this is a sign the belt is not tracking properly and this is due to an accessory drive with too much bearing/shaft play.
If the noise is still present with the belt removed then you need to install the belt and look elsewhere for the source of the noise.
If you suspect it is a transmission noise then it should be affected if the clutch pedal is fully up vs. fully down.
If pushing the clutch pedal all the way down and having it all the way up doesn't affect the noise then almost certainly it is coming from inside the engine.
If you suspect the noise is coming from inside the engine this is a pretty serious condition -- which may be addressable -- but the proper diagnosis and repair is probably beyond your capability.
In this case I advise you seek out a highly skilled/qualified tech (dealer or indy) and have him listen and make a diagnosis and advise you.
#23
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You can change the transmission fluid if you want but I don't think it will help. I've run the gear oil in my cars for a long time -- up to 90K miles in at least one instance -- without the tranny making any noise.
(My advice would be to just use the Porsche fluid as it will be miscible with the fluid that is in the transmission currently and properly suited for use with the transmission. There is no need to question whether you need LSD compatible fluid or some other kind.)
When trying to identify a noise source be sure the A/C is off and the radiator fans are off. The fans run all the time the A/C is on even if the engine is cold.
If the noise is present from a cold start one thing you can do is remove the serpentine belt -- make a diagram of the routing of the belt and its direction of rotation so you can reinstall the belt the same way it came off -- and start the engine and let it idle only long enough to confirm the noise is absent or still present.
If absent then likely an accessory drive idler/tensioner roller bearing is bad (noisy and noisy is bad) or an accessory drive is bad. Most often in this case the water pump is the guilty accessory drive.
Check all for any excessive play. The water pump may not have lots of play but it can have -- at least in my experience -- a bit more play than the other drives which essentially had none.
Also, if the belt has a sharp edge this is a sign the belt is not tracking properly and this is due to an accessory drive with too much bearing/shaft play.
If the noise is still present with the belt removed then you need to install the belt and look elsewhere for the source of the noise.
If you suspect it is a transmission noise then it should be affected if the clutch pedal is fully up vs. fully down.
If pushing the clutch pedal all the way down and having it all the way up doesn't affect the noise then almost certainly it is coming from inside the engine.
If you suspect the noise is coming from inside the engine this is a pretty serious condition -- which may be addressable -- but the proper diagnosis and repair is probably beyond your capability.
In this case I advise you seek out a highly skilled/qualified tech (dealer or indy) and have him listen and make a diagnosis and advise you.
(My advice would be to just use the Porsche fluid as it will be miscible with the fluid that is in the transmission currently and properly suited for use with the transmission. There is no need to question whether you need LSD compatible fluid or some other kind.)
When trying to identify a noise source be sure the A/C is off and the radiator fans are off. The fans run all the time the A/C is on even if the engine is cold.
If the noise is present from a cold start one thing you can do is remove the serpentine belt -- make a diagram of the routing of the belt and its direction of rotation so you can reinstall the belt the same way it came off -- and start the engine and let it idle only long enough to confirm the noise is absent or still present.
If absent then likely an accessory drive idler/tensioner roller bearing is bad (noisy and noisy is bad) or an accessory drive is bad. Most often in this case the water pump is the guilty accessory drive.
Check all for any excessive play. The water pump may not have lots of play but it can have -- at least in my experience -- a bit more play than the other drives which essentially had none.
Also, if the belt has a sharp edge this is a sign the belt is not tracking properly and this is due to an accessory drive with too much bearing/shaft play.
If the noise is still present with the belt removed then you need to install the belt and look elsewhere for the source of the noise.
If you suspect it is a transmission noise then it should be affected if the clutch pedal is fully up vs. fully down.
If pushing the clutch pedal all the way down and having it all the way up doesn't affect the noise then almost certainly it is coming from inside the engine.
If you suspect the noise is coming from inside the engine this is a pretty serious condition -- which may be addressable -- but the proper diagnosis and repair is probably beyond your capability.
In this case I advise you seek out a highly skilled/qualified tech (dealer or indy) and have him listen and make a diagnosis and advise you.
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